corrected example one; error: x.sort() doesn't return the array, just modifies it; modified print-function in example 3 according to python3-syntax; corrected example 3; error: the trapz-functions was used with flipped arguments, the y-arg has to be given first
corrected example 2; error: new_values and values were the same object, values had to be explicitly copied to new_values; furthermore corrected print-function according to python3-syntax